In Phase I research, we propose to combine gel microdrop (GMD) single cell encapsulation and flow cytometry to distinguish telomerase positive cells present in a heterogenous population. Detection of telomerase expression at the mRNA level will permit discrimination of previously undetectable tumor cells both in blood and in benign tissues. It can also be used as an informative marker of residual disease for patients undergoing chemotherapy. Since telomerase positive cells are present within a heterogenous population, an in situ assay capable of precisely detecting and isolating telomerase labeled cells would be broadly applicable for future studies in clinical oncology. PROPOSED COMMERCIAL APPLICATION The ability to detect small sub-populations of cells which are positive for telomerase activity would be a significant advance in clinical diagnostics. Early detection of cancer would improve health care.